Define population density, and describe the three different types of population distribution patterns. What will be an ideal response?
Population density is the number of individuals per unit area (or volume). Rare individuals
have a much lower population density than dominant ones. (1) A random distribution implies
that the position of one organism in a community in no way influences the position of other
organisms in the same community. A truly random distribution indicates that conditions are
precisely the same throughout the habitat, an extremely unlikely situation, except possibly in
the unvarying benthic communities of abyssal plains. (2) The most common pattern for
distribution of organisms is small patchy aggregations, or clumps. Clumped distribution
occurs when conditions for growth are optimal in small areas because of physical protection
(in cracks in an intertidal rock), nutrient concentration (near a dead body on the bottom),
initial dispersal (near the position of a parent), or social interaction. (3) Uniform distribution, with equal space between individuals, such as the arrangement of trees planted in orchards, is
the rarest natural pattern of all. The distribution of some garden eels through their territories
becomes almost uniform because each eel can extend from its burrow just far enough to
hassle neighbor eels spaced equally distant.
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The place within the Earth where rock ruptures and slips, or the place where an explosion occurs, is called:
a. Earthquake epicenter b. Earthquake focus c. Earthquake hypocenter d. Earthquake trace e. Both b and c
Although the soils of Central Asia's steppes are generally rich, much like those of the prairie lands of the U.S. Great Plains, a steppe environment differs from a prairie environment in its generally lower and more variable:
A) winds B) temperature C) precipitation D) tornadoes
The collective term for any process that produces a mountain belt is called ________
A) orogenesis B) diagenesis C) petrogenesis D) subduction
Which of the following is(are) involved in the breaking down of di- and polysaccharides to monosaccharides?
A) enzymes B) stomach acid C) both a and b D) neither a nor b